1255 lines
41 KiB
Python
1255 lines
41 KiB
Python
#
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# ElementTree
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# $Id: ElementTree.py 2326 2005-03-17 07:45:21Z fredrik $
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#
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# light-weight XML support for Python 1.5.2 and later.
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#
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# history:
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# 2001-10-20 fl created (from various sources)
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# 2001-11-01 fl return root from parse method
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# 2002-02-16 fl sort attributes in lexical order
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# 2002-04-06 fl TreeBuilder refactoring, added PythonDoc markup
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# 2002-05-01 fl finished TreeBuilder refactoring
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# 2002-07-14 fl added basic namespace support to ElementTree.write
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# 2002-07-25 fl added QName attribute support
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# 2002-10-20 fl fixed encoding in write
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# 2002-11-24 fl changed default encoding to ascii; fixed attribute encoding
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# 2002-11-27 fl accept file objects or file names for parse/write
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# 2002-12-04 fl moved XMLTreeBuilder back to this module
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# 2003-01-11 fl fixed entity encoding glitch for us-ascii
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# 2003-02-13 fl added XML literal factory
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# 2003-02-21 fl added ProcessingInstruction/PI factory
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# 2003-05-11 fl added tostring/fromstring helpers
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# 2003-05-26 fl added ElementPath support
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# 2003-07-05 fl added makeelement factory method
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# 2003-07-28 fl added more well-known namespace prefixes
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# 2003-08-15 fl fixed typo in ElementTree.findtext (Thomas Dartsch)
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# 2003-09-04 fl fall back on emulator if ElementPath is not installed
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# 2003-10-31 fl markup updates
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# 2003-11-15 fl fixed nested namespace bug
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# 2004-03-28 fl added XMLID helper
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# 2004-06-02 fl added default support to findtext
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# 2004-06-08 fl fixed encoding of non-ascii element/attribute names
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# 2004-08-23 fl take advantage of post-2.1 expat features
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# 2005-02-01 fl added iterparse implementation
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# 2005-03-02 fl fixed iterparse support for pre-2.2 versions
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#
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# Copyright (c) 1999-2005 by Fredrik Lundh. All rights reserved.
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#
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# fredrik@pythonware.com
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# http://www.pythonware.com
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#
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# --------------------------------------------------------------------
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# The ElementTree toolkit is
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#
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# Copyright (c) 1999-2005 by Fredrik Lundh
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#
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# By obtaining, using, and/or copying this software and/or its
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# associated documentation, you agree that you have read, understood,
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# and will comply with the following terms and conditions:
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#
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# Permission to use, copy, modify, and distribute this software and
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# its associated documentation for any purpose and without fee is
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# hereby granted, provided that the above copyright notice appears in
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# all copies, and that both that copyright notice and this permission
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# notice appear in supporting documentation, and that the name of
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# Secret Labs AB or the author not be used in advertising or publicity
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# pertaining to distribution of the software without specific, written
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# prior permission.
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#
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# SECRET LABS AB AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD
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# TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANT-
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# ABILITY AND FITNESS. IN NO EVENT SHALL SECRET LABS AB OR THE AUTHOR
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# BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
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# DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
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# WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
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# ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
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# OF THIS SOFTWARE.
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# --------------------------------------------------------------------
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__all__ = [
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# public symbols
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"Comment",
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"dump",
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"Element", "ElementTree",
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"fromstring",
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"iselement", "iterparse",
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"parse",
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"PI", "ProcessingInstruction",
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"QName",
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"SubElement",
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"tostring",
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"TreeBuilder",
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"VERSION", "XML",
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"XMLTreeBuilder",
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]
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##
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# The <b>Element</b> type is a flexible container object, designed to
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# store hierarchical data structures in memory. The type can be
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# described as a cross between a list and a dictionary.
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# <p>
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# Each element has a number of properties associated with it:
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# <ul>
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# <li>a <i>tag</i>. This is a string identifying what kind of data
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# this element represents (the element type, in other words).</li>
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# <li>a number of <i>attributes</i>, stored in a Python dictionary.</li>
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# <li>a <i>text</i> string.</li>
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# <li>an optional <i>tail</i> string.</li>
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# <li>a number of <i>child elements</i>, stored in a Python sequence</li>
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# </ul>
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#
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# To create an element instance, use the {@link #Element} or {@link
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# #SubElement} factory functions.
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# <p>
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# The {@link #ElementTree} class can be used to wrap an element
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# structure, and convert it from and to XML.
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##
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import string, sys, re
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class _SimpleElementPath:
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# emulate pre-1.2 find/findtext/findall behaviour
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def find(self, element, tag):
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for elem in element:
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if elem.tag == tag:
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return elem
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return None
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def findtext(self, element, tag, default=None):
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for elem in element:
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if elem.tag == tag:
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return elem.text or ""
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return default
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def findall(self, element, tag):
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if tag[:3] == ".//":
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return element.getiterator(tag[3:])
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result = []
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for elem in element:
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if elem.tag == tag:
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result.append(elem)
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return result
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try:
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import ElementPath
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except ImportError:
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# FIXME: issue warning in this case?
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ElementPath = _SimpleElementPath()
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# TODO: add support for custom namespace resolvers/default namespaces
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# TODO: add improved support for incremental parsing
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VERSION = "1.2.6"
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##
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# Internal element class. This class defines the Element interface,
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# and provides a reference implementation of this interface.
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# <p>
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# You should not create instances of this class directly. Use the
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# appropriate factory functions instead, such as {@link #Element}
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# and {@link #SubElement}.
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#
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# @see Element
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# @see SubElement
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# @see Comment
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# @see ProcessingInstruction
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class _ElementInterface:
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# <tag attrib>text<child/>...</tag>tail
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##
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# (Attribute) Element tag.
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tag = None
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##
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# (Attribute) Element attribute dictionary. Where possible, use
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# {@link #_ElementInterface.get},
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# {@link #_ElementInterface.set},
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# {@link #_ElementInterface.keys}, and
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# {@link #_ElementInterface.items} to access
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# element attributes.
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attrib = None
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##
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# (Attribute) Text before first subelement. This is either a
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# string or the value None, if there was no text.
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text = None
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##
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# (Attribute) Text after this element's end tag, but before the
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# next sibling element's start tag. This is either a string or
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# the value None, if there was no text.
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tail = None # text after end tag, if any
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def __init__(self, tag, attrib):
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self.tag = tag
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self.attrib = attrib
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self._children = []
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def __repr__(self):
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return "<Element %s at %x>" % (self.tag, id(self))
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##
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# Creates a new element object of the same type as this element.
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#
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# @param tag Element tag.
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# @param attrib Element attributes, given as a dictionary.
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# @return A new element instance.
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def makeelement(self, tag, attrib):
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return Element(tag, attrib)
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##
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# Returns the number of subelements.
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#
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# @return The number of subelements.
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def __len__(self):
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return len(self._children)
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##
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# Returns the given subelement.
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#
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# @param index What subelement to return.
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# @return The given subelement.
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# @exception IndexError If the given element does not exist.
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def __getitem__(self, index):
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return self._children[index]
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##
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# Replaces the given subelement.
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#
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# @param index What subelement to replace.
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# @param element The new element value.
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# @exception IndexError If the given element does not exist.
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# @exception AssertionError If element is not a valid object.
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def __setitem__(self, index, element):
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assert iselement(element)
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self._children[index] = element
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##
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# Deletes the given subelement.
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#
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# @param index What subelement to delete.
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# @exception IndexError If the given element does not exist.
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def __delitem__(self, index):
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del self._children[index]
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##
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# Returns a list containing subelements in the given range.
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#
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# @param start The first subelement to return.
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# @param stop The first subelement that shouldn't be returned.
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# @return A sequence object containing subelements.
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def __getslice__(self, start, stop):
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return self._children[start:stop]
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##
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# Replaces a number of subelements with elements from a sequence.
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#
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# @param start The first subelement to replace.
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# @param stop The first subelement that shouldn't be replaced.
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# @param elements A sequence object with zero or more elements.
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# @exception AssertionError If a sequence member is not a valid object.
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def __setslice__(self, start, stop, elements):
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for element in elements:
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assert iselement(element)
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self._children[start:stop] = list(elements)
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##
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# Deletes a number of subelements.
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#
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# @param start The first subelement to delete.
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# @param stop The first subelement to leave in there.
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def __delslice__(self, start, stop):
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del self._children[start:stop]
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##
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# Adds a subelement to the end of this element.
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#
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# @param element The element to add.
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# @exception AssertionError If a sequence member is not a valid object.
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def append(self, element):
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assert iselement(element)
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self._children.append(element)
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##
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# Inserts a subelement at the given position in this element.
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#
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# @param index Where to insert the new subelement.
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# @exception AssertionError If the element is not a valid object.
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def insert(self, index, element):
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assert iselement(element)
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self._children.insert(index, element)
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##
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# Removes a matching subelement. Unlike the <b>find</b> methods,
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# this method compares elements based on identity, not on tag
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# value or contents.
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#
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# @param element What element to remove.
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# @exception ValueError If a matching element could not be found.
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# @exception AssertionError If the element is not a valid object.
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def remove(self, element):
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assert iselement(element)
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self._children.remove(element)
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##
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# Returns all subelements. The elements are returned in document
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# order.
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#
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# @return A list of subelements.
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# @defreturn list of Element instances
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def getchildren(self):
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return self._children
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##
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# Finds the first matching subelement, by tag name or path.
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#
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# @param path What element to look for.
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# @return The first matching element, or None if no element was found.
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# @defreturn Element or None
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def find(self, path):
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return ElementPath.find(self, path)
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##
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# Finds text for the first matching subelement, by tag name or path.
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#
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# @param path What element to look for.
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# @param default What to return if the element was not found.
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# @return The text content of the first matching element, or the
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# default value no element was found. Note that if the element
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# has is found, but has no text content, this method returns an
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# empty string.
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# @defreturn string
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def findtext(self, path, default=None):
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return ElementPath.findtext(self, path, default)
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##
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# Finds all matching subelements, by tag name or path.
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#
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# @param path What element to look for.
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# @return A list or iterator containing all matching elements,
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# in document order.
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# @defreturn list of Element instances
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def findall(self, path):
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return ElementPath.findall(self, path)
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##
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# Resets an element. This function removes all subelements, clears
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# all attributes, and sets the text and tail attributes to None.
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def clear(self):
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self.attrib.clear()
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self._children = []
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self.text = self.tail = None
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##
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# Gets an element attribute.
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#
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# @param key What attribute to look for.
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# @param default What to return if the attribute was not found.
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# @return The attribute value, or the default value, if the
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# attribute was not found.
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# @defreturn string or None
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def get(self, key, default=None):
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return self.attrib.get(key, default)
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##
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# Sets an element attribute.
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#
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# @param key What attribute to set.
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# @param value The attribute value.
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def set(self, key, value):
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self.attrib[key] = value
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##
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# Gets a list of attribute names. The names are returned in an
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# arbitrary order (just like for an ordinary Python dictionary).
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#
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# @return A list of element attribute names.
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# @defreturn list of strings
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def keys(self):
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return self.attrib.keys()
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##
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# Gets element attributes, as a sequence. The attributes are
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# returned in an arbitrary order.
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#
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# @return A list of (name, value) tuples for all attributes.
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# @defreturn list of (string, string) tuples
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def items(self):
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return self.attrib.items()
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##
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# Creates a tree iterator. The iterator loops over this element
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# and all subelements, in document order, and returns all elements
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# with a matching tag.
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# <p>
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# If the tree structure is modified during iteration, the result
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# is undefined.
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#
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# @param tag What tags to look for (default is to return all elements).
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# @return A list or iterator containing all the matching elements.
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# @defreturn list or iterator
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def getiterator(self, tag=None):
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nodes = []
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if tag == "*":
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tag = None
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if tag is None or self.tag == tag:
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nodes.append(self)
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for node in self._children:
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nodes.extend(node.getiterator(tag))
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return nodes
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# compatibility
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_Element = _ElementInterface
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##
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# Element factory. This function returns an object implementing the
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# standard Element interface. The exact class or type of that object
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# is implementation dependent, but it will always be compatible with
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# the {@link #_ElementInterface} class in this module.
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# <p>
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# The element name, attribute names, and attribute values can be
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# either 8-bit ASCII strings or Unicode strings.
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#
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# @param tag The element name.
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# @param attrib An optional dictionary, containing element attributes.
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# @param **extra Additional attributes, given as keyword arguments.
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# @return An element instance.
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# @defreturn Element
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def Element(tag, attrib={}, **extra):
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attrib = attrib.copy()
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attrib.update(extra)
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return _ElementInterface(tag, attrib)
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|
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##
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# Subelement factory. This function creates an element instance, and
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# appends it to an existing element.
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# <p>
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# The element name, attribute names, and attribute values can be
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# either 8-bit ASCII strings or Unicode strings.
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#
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# @param parent The parent element.
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# @param tag The subelement name.
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# @param attrib An optional dictionary, containing element attributes.
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# @param **extra Additional attributes, given as keyword arguments.
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# @return An element instance.
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# @defreturn Element
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def SubElement(parent, tag, attrib={}, **extra):
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attrib = attrib.copy()
|
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attrib.update(extra)
|
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element = parent.makeelement(tag, attrib)
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parent.append(element)
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return element
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|
|
##
|
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# Comment element factory. This factory function creates a special
|
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# element that will be serialized as an XML comment.
|
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# <p>
|
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# The comment string can be either an 8-bit ASCII string or a Unicode
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# string.
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#
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# @param text A string containing the comment string.
|
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# @return An element instance, representing a comment.
|
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# @defreturn Element
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|
|
|
def Comment(text=None):
|
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element = Element(Comment)
|
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element.text = text
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return element
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|
|
|
##
|
|
# PI element factory. This factory function creates a special element
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|
# that will be serialized as an XML processing instruction.
|
|
#
|
|
# @param target A string containing the PI target.
|
|
# @param text A string containing the PI contents, if any.
|
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# @return An element instance, representing a PI.
|
|
# @defreturn Element
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|
|
|
def ProcessingInstruction(target, text=None):
|
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element = Element(ProcessingInstruction)
|
|
element.text = target
|
|
if text:
|
|
element.text = element.text + " " + text
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|
return element
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|
|
|
PI = ProcessingInstruction
|
|
|
|
##
|
|
# QName wrapper. This can be used to wrap a QName attribute value, in
|
|
# order to get proper namespace handling on output.
|
|
#
|
|
# @param text A string containing the QName value, in the form {uri}local,
|
|
# or, if the tag argument is given, the URI part of a QName.
|
|
# @param tag Optional tag. If given, the first argument is interpreted as
|
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# an URI, and this argument is interpreted as a local name.
|
|
# @return An opaque object, representing the QName.
|
|
|
|
class QName:
|
|
def __init__(self, text_or_uri, tag=None):
|
|
if tag:
|
|
text_or_uri = "{%s}%s" % (text_or_uri, tag)
|
|
self.text = text_or_uri
|
|
def __str__(self):
|
|
return self.text
|
|
def __hash__(self):
|
|
return hash(self.text)
|
|
def __cmp__(self, other):
|
|
if isinstance(other, QName):
|
|
return cmp(self.text, other.text)
|
|
return cmp(self.text, other)
|
|
|
|
##
|
|
# ElementTree wrapper class. This class represents an entire element
|
|
# hierarchy, and adds some extra support for serialization to and from
|
|
# standard XML.
|
|
#
|
|
# @param element Optional root element.
|
|
# @keyparam file Optional file handle or name. If given, the
|
|
# tree is initialized with the contents of this XML file.
|
|
|
|
class ElementTree:
|
|
|
|
def __init__(self, element=None, file=None):
|
|
assert element is None or iselement(element)
|
|
self._root = element # first node
|
|
if file:
|
|
self.parse(file)
|
|
|
|
##
|
|
# Gets the root element for this tree.
|
|
#
|
|
# @return An element instance.
|
|
# @defreturn Element
|
|
|
|
def getroot(self):
|
|
return self._root
|
|
|
|
##
|
|
# Replaces the root element for this tree. This discards the
|
|
# current contents of the tree, and replaces it with the given
|
|
# element. Use with care.
|
|
#
|
|
# @param element An element instance.
|
|
|
|
def _setroot(self, element):
|
|
assert iselement(element)
|
|
self._root = element
|
|
|
|
##
|
|
# Loads an external XML document into this element tree.
|
|
#
|
|
# @param source A file name or file object.
|
|
# @param parser An optional parser instance. If not given, the
|
|
# standard {@link XMLTreeBuilder} parser is used.
|
|
# @return The document root element.
|
|
# @defreturn Element
|
|
|
|
def parse(self, source, parser=None):
|
|
if not hasattr(source, "read"):
|
|
source = open(source, "rb")
|
|
if not parser:
|
|
parser = XMLTreeBuilder()
|
|
while 1:
|
|
data = source.read(32768)
|
|
if not data:
|
|
break
|
|
parser.feed(data)
|
|
self._root = parser.close()
|
|
return self._root
|
|
|
|
##
|
|
# Creates a tree iterator for the root element. The iterator loops
|
|
# over all elements in this tree, in document order.
|
|
#
|
|
# @param tag What tags to look for (default is to return all elements)
|
|
# @return An iterator.
|
|
# @defreturn iterator
|
|
|
|
def getiterator(self, tag=None):
|
|
assert self._root is not None
|
|
return self._root.getiterator(tag)
|
|
|
|
##
|
|
# Finds the first toplevel element with given tag.
|
|
# Same as getroot().find(path).
|
|
#
|
|
# @param path What element to look for.
|
|
# @return The first matching element, or None if no element was found.
|
|
# @defreturn Element or None
|
|
|
|
def find(self, path):
|
|
assert self._root is not None
|
|
if path[:1] == "/":
|
|
path = "." + path
|
|
return self._root.find(path)
|
|
|
|
##
|
|
# Finds the element text for the first toplevel element with given
|
|
# tag. Same as getroot().findtext(path).
|
|
#
|
|
# @param path What toplevel element to look for.
|
|
# @param default What to return if the element was not found.
|
|
# @return The text content of the first matching element, or the
|
|
# default value no element was found. Note that if the element
|
|
# has is found, but has no text content, this method returns an
|
|
# empty string.
|
|
# @defreturn string
|
|
|
|
def findtext(self, path, default=None):
|
|
assert self._root is not None
|
|
if path[:1] == "/":
|
|
path = "." + path
|
|
return self._root.findtext(path, default)
|
|
|
|
##
|
|
# Finds all toplevel elements with the given tag.
|
|
# Same as getroot().findall(path).
|
|
#
|
|
# @param path What element to look for.
|
|
# @return A list or iterator containing all matching elements,
|
|
# in document order.
|
|
# @defreturn list of Element instances
|
|
|
|
def findall(self, path):
|
|
assert self._root is not None
|
|
if path[:1] == "/":
|
|
path = "." + path
|
|
return self._root.findall(path)
|
|
|
|
##
|
|
# Writes the element tree to a file, as XML.
|
|
#
|
|
# @param file A file name, or a file object opened for writing.
|
|
# @param encoding Optional output encoding (default is US-ASCII).
|
|
|
|
def write(self, file, encoding="us-ascii"):
|
|
assert self._root is not None
|
|
if not hasattr(file, "write"):
|
|
file = open(file, "wb")
|
|
if not encoding:
|
|
encoding = "us-ascii"
|
|
elif encoding != "utf-8" and encoding != "us-ascii":
|
|
file.write("<?xml version='1.0' encoding='%s'?>\n" % encoding)
|
|
self._write(file, self._root, encoding, {})
|
|
|
|
def _write(self, file, node, encoding, namespaces):
|
|
# write XML to file
|
|
tag = node.tag
|
|
if tag is Comment:
|
|
file.write("<!-- %s -->" % _escape_cdata(node.text, encoding))
|
|
elif tag is ProcessingInstruction:
|
|
file.write("<?%s?>" % _escape_cdata(node.text, encoding))
|
|
else:
|
|
items = node.items()
|
|
xmlns_items = [] # new namespaces in this scope
|
|
try:
|
|
if isinstance(tag, QName) or tag[:1] == "{":
|
|
tag, xmlns = fixtag(tag, namespaces)
|
|
if xmlns: xmlns_items.append(xmlns)
|
|
except TypeError:
|
|
_raise_serialization_error(tag)
|
|
file.write("<" + _encode(tag, encoding))
|
|
if items or xmlns_items:
|
|
items.sort() # lexical order
|
|
for k, v in items:
|
|
try:
|
|
if isinstance(k, QName) or k[:1] == "{":
|
|
k, xmlns = fixtag(k, namespaces)
|
|
if xmlns: xmlns_items.append(xmlns)
|
|
except TypeError:
|
|
_raise_serialization_error(k)
|
|
try:
|
|
if isinstance(v, QName):
|
|
v, xmlns = fixtag(v, namespaces)
|
|
if xmlns: xmlns_items.append(xmlns)
|
|
except TypeError:
|
|
_raise_serialization_error(v)
|
|
file.write(" %s=\"%s\"" % (_encode(k, encoding),
|
|
_escape_attrib(v, encoding)))
|
|
for k, v in xmlns_items:
|
|
file.write(" %s=\"%s\"" % (_encode(k, encoding),
|
|
_escape_attrib(v, encoding)))
|
|
if node.text or len(node):
|
|
file.write(">")
|
|
if node.text:
|
|
file.write(_escape_cdata(node.text, encoding))
|
|
for n in node:
|
|
self._write(file, n, encoding, namespaces)
|
|
file.write("</" + _encode(tag, encoding) + ">")
|
|
else:
|
|
file.write(" />")
|
|
for k, v in xmlns_items:
|
|
del namespaces[v]
|
|
if node.tail:
|
|
file.write(_escape_cdata(node.tail, encoding))
|
|
|
|
# --------------------------------------------------------------------
|
|
# helpers
|
|
|
|
##
|
|
# Checks if an object appears to be a valid element object.
|
|
#
|
|
# @param An element instance.
|
|
# @return A true value if this is an element object.
|
|
# @defreturn flag
|
|
|
|
def iselement(element):
|
|
# FIXME: not sure about this; might be a better idea to look
|
|
# for tag/attrib/text attributes
|
|
return isinstance(element, _ElementInterface) or hasattr(element, "tag")
|
|
|
|
##
|
|
# Writes an element tree or element structure to sys.stdout. This
|
|
# function should be used for debugging only.
|
|
# <p>
|
|
# The exact output format is implementation dependent. In this
|
|
# version, it's written as an ordinary XML file.
|
|
#
|
|
# @param elem An element tree or an individual element.
|
|
|
|
def dump(elem):
|
|
# debugging
|
|
if not isinstance(elem, ElementTree):
|
|
elem = ElementTree(elem)
|
|
elem.write(sys.stdout)
|
|
tail = elem.getroot().tail
|
|
if not tail or tail[-1] != "\n":
|
|
sys.stdout.write("\n")
|
|
|
|
def _encode(s, encoding):
|
|
try:
|
|
return s.encode(encoding)
|
|
except AttributeError:
|
|
return s # 1.5.2: assume the string uses the right encoding
|
|
|
|
if sys.version[:3] == "1.5":
|
|
_escape = re.compile(r"[&<>\"\x80-\xff]+") # 1.5.2
|
|
else:
|
|
_escape = re.compile(eval(r'u"[&<>\"\u0080-\uffff]+"'))
|
|
|
|
_escape_map = {
|
|
"&": "&",
|
|
"<": "<",
|
|
">": ">",
|
|
'"': """,
|
|
}
|
|
|
|
_namespace_map = {
|
|
# "well-known" namespace prefixes
|
|
"http://www.w3.org/XML/1998/namespace": "xml",
|
|
"http://www.w3.org/1999/xhtml": "html",
|
|
"http://www.w3.org/1999/02/22-rdf-syntax-ns#": "rdf",
|
|
"http://schemas.xmlsoap.org/wsdl/": "wsdl",
|
|
}
|
|
|
|
def _raise_serialization_error(text):
|
|
raise TypeError(
|
|
"cannot serialize %r (type %s)" % (text, type(text).__name__)
|
|
)
|
|
|
|
def _encode_entity(text, pattern=_escape):
|
|
# map reserved and non-ascii characters to numerical entities
|
|
def escape_entities(m, map=_escape_map):
|
|
out = []
|
|
append = out.append
|
|
for char in m.group():
|
|
text = map.get(char)
|
|
if text is None:
|
|
text = "&#%d;" % ord(char)
|
|
append(text)
|
|
return string.join(out, "")
|
|
try:
|
|
return _encode(pattern.sub(escape_entities, text), "ascii")
|
|
except TypeError:
|
|
_raise_serialization_error(text)
|
|
|
|
#
|
|
# the following functions assume an ascii-compatible encoding
|
|
# (or "utf-16")
|
|
|
|
def _escape_cdata(text, encoding=None, replace=string.replace):
|
|
# escape character data
|
|
try:
|
|
if encoding:
|
|
try:
|
|
text = _encode(text, encoding)
|
|
except UnicodeError:
|
|
return _encode_entity(text)
|
|
text = replace(text, "&", "&")
|
|
text = replace(text, "<", "<")
|
|
text = replace(text, ">", ">")
|
|
return text
|
|
except (TypeError, AttributeError):
|
|
_raise_serialization_error(text)
|
|
|
|
def _escape_attrib(text, encoding=None, replace=string.replace):
|
|
# escape attribute value
|
|
try:
|
|
if encoding:
|
|
try:
|
|
text = _encode(text, encoding)
|
|
except UnicodeError:
|
|
return _encode_entity(text)
|
|
text = replace(text, "&", "&")
|
|
text = replace(text, "'", "'") # FIXME: overkill
|
|
text = replace(text, "\"", """)
|
|
text = replace(text, "<", "<")
|
|
text = replace(text, ">", ">")
|
|
return text
|
|
except (TypeError, AttributeError):
|
|
_raise_serialization_error(text)
|
|
|
|
def fixtag(tag, namespaces):
|
|
# given a decorated tag (of the form {uri}tag), return prefixed
|
|
# tag and namespace declaration, if any
|
|
if isinstance(tag, QName):
|
|
tag = tag.text
|
|
namespace_uri, tag = string.split(tag[1:], "}", 1)
|
|
prefix = namespaces.get(namespace_uri)
|
|
if prefix is None:
|
|
prefix = _namespace_map.get(namespace_uri)
|
|
if prefix is None:
|
|
prefix = "ns%d" % len(namespaces)
|
|
namespaces[namespace_uri] = prefix
|
|
if prefix == "xml":
|
|
xmlns = None
|
|
else:
|
|
xmlns = ("xmlns:%s" % prefix, namespace_uri)
|
|
else:
|
|
xmlns = None
|
|
return "%s:%s" % (prefix, tag), xmlns
|
|
|
|
##
|
|
# Parses an XML document into an element tree.
|
|
#
|
|
# @param source A filename or file object containing XML data.
|
|
# @param parser An optional parser instance. If not given, the
|
|
# standard {@link XMLTreeBuilder} parser is used.
|
|
# @return An ElementTree instance
|
|
|
|
def parse(source, parser=None):
|
|
tree = ElementTree()
|
|
tree.parse(source, parser)
|
|
return tree
|
|
|
|
##
|
|
# Parses an XML document into an element tree incrementally, and reports
|
|
# what's going on to the user.
|
|
#
|
|
# @param source A filename or file object containing XML data.
|
|
# @param events A list of events to report back. If omitted, only "end"
|
|
# events are reported.
|
|
# @return A (event, elem) iterator.
|
|
|
|
class iterparse:
|
|
|
|
def __init__(self, source, events=None):
|
|
if not hasattr(source, "read"):
|
|
source = open(source, "rb")
|
|
self._file = source
|
|
self._events = []
|
|
self._index = 0
|
|
self.root = self._root = None
|
|
self._parser = XMLTreeBuilder()
|
|
# wire up the parser for event reporting
|
|
parser = self._parser._parser
|
|
append = self._events.append
|
|
if events is None:
|
|
events = ["end"]
|
|
for event in events:
|
|
if event == "start":
|
|
try:
|
|
parser.ordered_attributes = 1
|
|
parser.specified_attributes = 1
|
|
def handler(tag, attrib_in, event=event, append=append,
|
|
start=self._parser._start_list):
|
|
append((event, start(tag, attrib_in)))
|
|
parser.StartElementHandler = handler
|
|
except AttributeError:
|
|
def handler(tag, attrib_in, event=event, append=append,
|
|
start=self._parser._start):
|
|
append((event, start(tag, attrib_in)))
|
|
parser.StartElementHandler = handler
|
|
elif event == "end":
|
|
def handler(tag, event=event, append=append,
|
|
end=self._parser._end):
|
|
append((event, end(tag)))
|
|
parser.EndElementHandler = handler
|
|
elif event == "start-ns":
|
|
def handler(prefix, uri, event=event, append=append):
|
|
try:
|
|
uri = _encode(uri, "ascii")
|
|
except UnicodeError:
|
|
pass
|
|
append((event, (prefix or "", uri)))
|
|
parser.StartNamespaceDeclHandler = handler
|
|
elif event == "end-ns":
|
|
def handler(prefix, event=event, append=append):
|
|
append((event, None))
|
|
parser.EndNamespaceDeclHandler = handler
|
|
|
|
def next(self):
|
|
while 1:
|
|
try:
|
|
item = self._events[self._index]
|
|
except IndexError:
|
|
if self._parser is None:
|
|
self.root = self._root
|
|
try:
|
|
raise StopIteration
|
|
except NameError:
|
|
raise IndexError
|
|
# load event buffer
|
|
del self._events[:]
|
|
self._index = 0
|
|
data = self._file.read(16384)
|
|
if data:
|
|
self._parser.feed(data)
|
|
else:
|
|
self._root = self._parser.close()
|
|
self._parser = None
|
|
else:
|
|
self._index = self._index + 1
|
|
return item
|
|
|
|
try:
|
|
iter
|
|
def __iter__(self):
|
|
return self
|
|
except NameError:
|
|
def __getitem__(self, index):
|
|
return self.next()
|
|
|
|
##
|
|
# Parses an XML document from a string constant. This function can
|
|
# be used to embed "XML literals" in Python code.
|
|
#
|
|
# @param source A string containing XML data.
|
|
# @return An Element instance.
|
|
# @defreturn Element
|
|
|
|
def XML(text):
|
|
parser = XMLTreeBuilder()
|
|
parser.feed(text)
|
|
return parser.close()
|
|
|
|
##
|
|
# Parses an XML document from a string constant, and also returns
|
|
# a dictionary which maps from element id:s to elements.
|
|
#
|
|
# @param source A string containing XML data.
|
|
# @return A tuple containing an Element instance and a dictionary.
|
|
# @defreturn (Element, dictionary)
|
|
|
|
def XMLID(text):
|
|
parser = XMLTreeBuilder()
|
|
parser.feed(text)
|
|
tree = parser.close()
|
|
ids = {}
|
|
for elem in tree.getiterator():
|
|
id = elem.get("id")
|
|
if id:
|
|
ids[id] = elem
|
|
return tree, ids
|
|
|
|
##
|
|
# Parses an XML document from a string constant. Same as {@link #XML}.
|
|
#
|
|
# @def fromstring(text)
|
|
# @param source A string containing XML data.
|
|
# @return An Element instance.
|
|
# @defreturn Element
|
|
|
|
fromstring = XML
|
|
|
|
##
|
|
# Generates a string representation of an XML element, including all
|
|
# subelements.
|
|
#
|
|
# @param element An Element instance.
|
|
# @return An encoded string containing the XML data.
|
|
# @defreturn string
|
|
|
|
def tostring(element, encoding=None):
|
|
class dummy:
|
|
pass
|
|
data = []
|
|
file = dummy()
|
|
file.write = data.append
|
|
ElementTree(element).write(file, encoding)
|
|
return string.join(data, "")
|
|
|
|
##
|
|
# Generic element structure builder. This builder converts a sequence
|
|
# of {@link #TreeBuilder.start}, {@link #TreeBuilder.data}, and {@link
|
|
# #TreeBuilder.end} method calls to a well-formed element structure.
|
|
# <p>
|
|
# You can use this class to build an element structure using a custom XML
|
|
# parser, or a parser for some other XML-like format.
|
|
#
|
|
# @param element_factory Optional element factory. This factory
|
|
# is called to create new Element instances, as necessary.
|
|
|
|
class TreeBuilder:
|
|
|
|
def __init__(self, element_factory=None):
|
|
self._data = [] # data collector
|
|
self._elem = [] # element stack
|
|
self._last = None # last element
|
|
self._tail = None # true if we're after an end tag
|
|
if element_factory is None:
|
|
element_factory = _ElementInterface
|
|
self._factory = element_factory
|
|
|
|
##
|
|
# Flushes the parser buffers, and returns the toplevel documen
|
|
# element.
|
|
#
|
|
# @return An Element instance.
|
|
# @defreturn Element
|
|
|
|
def close(self):
|
|
assert len(self._elem) == 0, "missing end tags"
|
|
assert self._last != None, "missing toplevel element"
|
|
return self._last
|
|
|
|
def _flush(self):
|
|
if self._data:
|
|
if self._last is not None:
|
|
text = string.join(self._data, "")
|
|
if self._tail:
|
|
assert self._last.tail is None, "internal error (tail)"
|
|
self._last.tail = text
|
|
else:
|
|
assert self._last.text is None, "internal error (text)"
|
|
self._last.text = text
|
|
self._data = []
|
|
|
|
##
|
|
# Adds text to the current element.
|
|
#
|
|
# @param data A string. This should be either an 8-bit string
|
|
# containing ASCII text, or a Unicode string.
|
|
|
|
def data(self, data):
|
|
self._data.append(data)
|
|
|
|
##
|
|
# Opens a new element.
|
|
#
|
|
# @param tag The element name.
|
|
# @param attrib A dictionary containing element attributes.
|
|
# @return The opened element.
|
|
# @defreturn Element
|
|
|
|
def start(self, tag, attrs):
|
|
self._flush()
|
|
self._last = elem = self._factory(tag, attrs)
|
|
if self._elem:
|
|
self._elem[-1].append(elem)
|
|
self._elem.append(elem)
|
|
self._tail = 0
|
|
return elem
|
|
|
|
##
|
|
# Closes the current element.
|
|
#
|
|
# @param tag The element name.
|
|
# @return The closed element.
|
|
# @defreturn Element
|
|
|
|
def end(self, tag):
|
|
self._flush()
|
|
self._last = self._elem.pop()
|
|
assert self._last.tag == tag,\
|
|
"end tag mismatch (expected %s, got %s)" % (
|
|
self._last.tag, tag)
|
|
self._tail = 1
|
|
return self._last
|
|
|
|
##
|
|
# Element structure builder for XML source data, based on the
|
|
# <b>expat</b> parser.
|
|
#
|
|
# @keyparam target Target object. If omitted, the builder uses an
|
|
# instance of the standard {@link #TreeBuilder} class.
|
|
# @keyparam html Predefine HTML entities. This flag is not supported
|
|
# by the current implementation.
|
|
# @see #ElementTree
|
|
# @see #TreeBuilder
|
|
|
|
class XMLTreeBuilder:
|
|
|
|
def __init__(self, html=0, target=None):
|
|
try:
|
|
from xml.parsers import expat
|
|
except ImportError:
|
|
raise ImportError(
|
|
"No module named expat; use SimpleXMLTreeBuilder instead"
|
|
)
|
|
self._parser = parser = expat.ParserCreate(None, "}")
|
|
if target is None:
|
|
target = TreeBuilder()
|
|
self._target = target
|
|
self._names = {} # name memo cache
|
|
# callbacks
|
|
parser.DefaultHandlerExpand = self._default
|
|
parser.StartElementHandler = self._start
|
|
parser.EndElementHandler = self._end
|
|
parser.CharacterDataHandler = self._data
|
|
# let expat do the buffering, if supported
|
|
try:
|
|
self._parser.buffer_text = 1
|
|
except AttributeError:
|
|
pass
|
|
# use new-style attribute handling, if supported
|
|
try:
|
|
self._parser.ordered_attributes = 1
|
|
self._parser.specified_attributes = 1
|
|
parser.StartElementHandler = self._start_list
|
|
except AttributeError:
|
|
pass
|
|
encoding = None
|
|
if not parser.returns_unicode:
|
|
encoding = "utf-8"
|
|
# target.xml(encoding, None)
|
|
self._doctype = None
|
|
self.entity = {}
|
|
|
|
def _fixtext(self, text):
|
|
# convert text string to ascii, if possible
|
|
try:
|
|
return _encode(text, "ascii")
|
|
except UnicodeError:
|
|
return text
|
|
|
|
def _fixname(self, key):
|
|
# expand qname, and convert name string to ascii, if possible
|
|
try:
|
|
name = self._names[key]
|
|
except KeyError:
|
|
name = key
|
|
if "}" in name:
|
|
name = "{" + name
|
|
self._names[key] = name = self._fixtext(name)
|
|
return name
|
|
|
|
def _start(self, tag, attrib_in):
|
|
fixname = self._fixname
|
|
tag = fixname(tag)
|
|
attrib = {}
|
|
for key, value in attrib_in.items():
|
|
attrib[fixname(key)] = self._fixtext(value)
|
|
return self._target.start(tag, attrib)
|
|
|
|
def _start_list(self, tag, attrib_in):
|
|
fixname = self._fixname
|
|
tag = fixname(tag)
|
|
attrib = {}
|
|
if attrib_in:
|
|
for i in range(0, len(attrib_in), 2):
|
|
attrib[fixname(attrib_in[i])] = self._fixtext(attrib_in[i+1])
|
|
return self._target.start(tag, attrib)
|
|
|
|
def _data(self, text):
|
|
return self._target.data(self._fixtext(text))
|
|
|
|
def _end(self, tag):
|
|
return self._target.end(self._fixname(tag))
|
|
|
|
def _default(self, text):
|
|
prefix = text[:1]
|
|
if prefix == "&":
|
|
# deal with undefined entities
|
|
try:
|
|
self._target.data(self.entity[text[1:-1]])
|
|
except KeyError:
|
|
from xml.parsers import expat
|
|
raise expat.error(
|
|
"undefined entity %s: line %d, column %d" %
|
|
(text, self._parser.ErrorLineNumber,
|
|
self._parser.ErrorColumnNumber)
|
|
)
|
|
elif prefix == "<" and text[:9] == "<!DOCTYPE":
|
|
self._doctype = [] # inside a doctype declaration
|
|
elif self._doctype is not None:
|
|
# parse doctype contents
|
|
if prefix == ">":
|
|
self._doctype = None
|
|
return
|
|
text = string.strip(text)
|
|
if not text:
|
|
return
|
|
self._doctype.append(text)
|
|
n = len(self._doctype)
|
|
if n > 2:
|
|
type = self._doctype[1]
|
|
if type == "PUBLIC" and n == 4:
|
|
name, type, pubid, system = self._doctype
|
|
elif type == "SYSTEM" and n == 3:
|
|
name, type, system = self._doctype
|
|
pubid = None
|
|
else:
|
|
return
|
|
if pubid:
|
|
pubid = pubid[1:-1]
|
|
self.doctype(name, pubid, system[1:-1])
|
|
self._doctype = None
|
|
|
|
##
|
|
# Handles a doctype declaration.
|
|
#
|
|
# @param name Doctype name.
|
|
# @param pubid Public identifier.
|
|
# @param system System identifier.
|
|
|
|
def doctype(self, name, pubid, system):
|
|
pass
|
|
|
|
##
|
|
# Feeds data to the parser.
|
|
#
|
|
# @param data Encoded data.
|
|
|
|
def feed(self, data):
|
|
self._parser.Parse(data, 0)
|
|
|
|
##
|
|
# Finishes feeding data to the parser.
|
|
#
|
|
# @return An element structure.
|
|
# @defreturn Element
|
|
|
|
def close(self):
|
|
self._parser.Parse("", 1) # end of data
|
|
tree = self._target.close()
|
|
del self._target, self._parser # get rid of circular references
|
|
return tree
|